In the field of optical communication, there is a pressing need to improve the capacity of optical networks. Increasing the capacity of the optical networks may be achieved by increasing the transmission rate in which the information is sent along the optical fibers of the networks. However, increasing the data rate in the optical communication networks faces several major and challenging obstacles, one of them among others, is the need to increasing the switching speed at the junctions and nodes distributed along the optical communication networks. The currently used optical communication networks already implemented the cutting edge technology in terms of switching speeds and operate at a rate to 10 Giga Bits Per Second (10 Gbps). The future goal is to move into higher rate of data that would be 40 Gbps. However, the technology for 40 Gbps is not available yet and it does not seem that it would be available, and for a reasonable price, in the near future. Thus, a solution for the need to increase the volume of the optical communication network should be done in a way that allows increasing the data transmission rate while still maintaining the available slower switching speed.
Increasing of the volume of the transmitted information without an increase of the switching speed may be achieved using Time Division Multiplexing (TDM) technique. According to the TDM technique, several data channels are interleaved, at one end of a transmission fiber, to create a single data channel operating at a rate that is higher than the rates of any of the interleaved channels. At the other end of the transmitting fiber, each of the interleaved channels is demultiplexed into a different port to operate there at its original data rate. The rate at the demultiplexed ports is low enough for being handled by the available switching speed. Thus the TDM technique allows high transmission rate, without degradation, even though the transmission rate is higher than the rate that the switches of the networks can handle. TDM in the optical domain saves the use of expensive Optical-Electrical-Optical (O-E-O) converters and allows applying the TDM technique on the optical pulses (bits) in the form that they are actually sent, resulting in a faster and cheaper operation.
Accordingly, it is an object of the present invention to provide an all-optical TDM system;
Another object of the present invention is to provide an all-optical TDM system capable of receiving and interleaving multiple data channels where each of the data channel operates at a certain data rate and sending the interleaved information of all the multiple data channels along a single data channel operating at a rate that is higher than the rate of any of the multiple data channels;
Another object of the present invention is to provide an all-optical TDM system capable of interleaving and demultiplexing multiple data channels;
Still another object of the present invention is to provide an all-optical TDM system capable of receiving multiple data channels at multiple inputs where each of the data channel operates at a certain data rate, sending the information of all the multiple interleaved channels along a single data channel operating at a data rate that is higher than each of the multiple interleaved data channels, and demultiplexing each of the multiple data channels from one input to one output.